Not a straightforward process. You might think you did well and see a different outcome. More like they already had in mind the candidate they wanted. To me, I feel it's not a straightforward process. And when they want to collate results, they usually want to go in the direction of the hiring manager. This is my opinion. I would love it if results are gotten independently.

I came in to interview for a technical management position but the actual position was more like program management. The first person I interview with was a VP and he didn't like me. Since interview feedback is shared forward and no one else would counter the VP I wasted a whole day interviewing for a job I couldn't get and which I didn't want. Sigh.